Investigation of Muscle Imbalance in the Leg in Symptomatic Forefoot Pes Cavus: A Multidisciplinary Study

Abstract

The cross-sectional areas of the peroneal and anterior muscle compartments at the same level in the upper leg were measured using magnetic resonance imaging in 41 cases of forefoot pes cavus. The pes cavus group included idiopathic cases and pes cavus associated with Charcot-Marie-Tooth disease, Friedreich's ataxia, cerebral palsy, status postpoliomyelitis, nerve trauma, and spinal cord tethering. Thirty-nine of these cases were symptomatic. The results were compared with studies of 11 normal controls. It was found that in the majority of cases of forefoot cavus, the peroneal compartment was enlarged relative to the anterior compartment when compared with the normal controls. Biopsies of the tibialis anterior and peroneus longus muscles in 18 patients with forefoot pes cavus showed that any relative expansion of the peroneus longus was not due to pseudohypertrophy. Overaction of the peroneus longus in comparison to its antagonist the tibialis anterior is proposed as an important factor in the pathogenesis of the majority of symptomatic cases of forefoot pes cavus.

Charcot–Marie–Tooth disease type 2J with MPZ Thr124Met mutation: clinico-electrophysiological and MRI study of a family

“…Chronic neuropathies developing before cessation of the growth period frequently give rise to foot deformity [1,42]. Forefoot pes cavus probably reflects muscle weakness and imbalance involving intrinsic foot musculature, lower leg musculature or both [44]. Presence of pes cavus is often taken as evidence of an inherited neuropathy such as CMT disease [25].…”

“…Forefoot pes cavus deformity is a cardinal manifestation of CMT [26,44]. Chronic neuropathies developing before cessation of the growth period frequently give rise to foot deformity [1,42].…”

Plantar pressure distribution analysis in normal weight young women and men with normal and claw feet: A cross-sectional study

“…This deformity is often associated with scoliosis and it may be secondary to altered balance or to disorders of the central nervous system, as shown by Carpintero et al (1994). In a multidisciplinary study of Tynan et al (1992), it was found that in the majority of cases of claw foot, the peroneal compartment was enlarged in relation to the anterior compartment when compared to the normal controls. Recent studies have shown that claw foot is one of the risk factors, including also flat foot, restricted ankle dorsiflexion, increased hind foot inversion, to predispose people toward lower extremity overuse injuries, as indicated by the studies of Kaufman et al (1999) and Keegan et al (2002).…”

The associations of leg lean mass with foot pain, posture and function in the Framingham foot study

“…Patients with CharcotMarie-Tooth disease, an inherited neurological disorder primarily affecting the peripheral nerves in the lower extremities, frequently exhibit pes cavus resulting from weakness in the peroneus brevis and tibialis anterior muscles relative to their natural antagonist tibialis posterior and peroneus longus muscles, respectively [17,18]. Similar imbalances in the peroneal and anterior compartments of the leg muscles have been shown to contribute to cases of pes cavus associated with other pathologies [16]. Additionally, young adults with pes planus demonstrated different sizes and thicknesses of the intrinsic and extrinsic muscles of the foot on ultrasound compared with normal controls [42].…”

“…Patients with posterior tibial tendon dysfunction, a common acquired flatfoot deformity, have lower ankle and hip muscle strength compared to non-patients [14], and the degree of deformity is inversely related to leg muscle strength [15]. Imbalance of the muscles that control the foot, but originate in the lower leg has been implicated in the etiology of both idiopathic and disease-related pes cavus (high arches) [16][17][18]. Further, evidence from studies of runners suggests that weakness in lower leg [19] and hip-stabilizing muscles [20] can lead to disturbed lower extremity mechanics, resulting in over-pronation of the foot.…”